7
necessary height and release it so that it free falls onto the
test surface. To subject LIBs to shock and vibration, a com-
mercially available hydraulic or electromechanical shaker
and a suitable controller will be purchased. The tempera-
ture/relative humidity chamber will be designed to encap-
sulate the moving portion of the shaker. The immersion test
apparatus will consist of a platform that lowers the tested
LIB into a suitably sized container of liquid.
During testing, the LIB will be monitored to exam-
ine surface and, possibly, internal temperatures. A thermal
imaging camera will be used for surface temperature mea-
surement. Multiple thermocouples will also be attached to
the battery case and, if possible, to cells within the bat-
tery case. Pressure sensors may also be used inside the
case because any venting of LIB cells inside is expected to
increase the internal pressure of the case. At this time, we
expect to conduct the tests with the battery management
system activated.
Numerous safety measures will be taken to protect
researchers and test equipment. The facility will use a video
monitoring system so that researchers can remain outside
the test chamber during tests. A ventilation system will be
installed to allow fresh air to flow into the test chamber and
contaminated air to flow out through an existing borehole.
Gas monitoring equipment will be installed within the test
chamber to ensure the atmosphere is safe for researchers to
enter.
Mine Utility Vehicle/Rubber-tired Mantrip Battery
Protection
To protect LIBs on MUVs/RTMs from excessive mechani-
cal shock and vibration, vibration isolation systems will be
designed. For this effort, dynamic simulation models of the
vehicles will be developed to predict the vibration response
at the LIB on the machine with and without vibration iso-
lators in place. Simulations will be conducted to determine
appropriate isolator parameters such as spring rate and
damping. Tire and suspension characteristics and vehicle
weight will be obtained from cooperating manufacturers or
determined via testing and measurement.
For the simulations, the approximate road inputs
will be derived from field conditions using measurements
of speed and resulting vibration response. In addition to
the shock and vibration recorded using the environmental
data recorders, on selected MUVs/RTMs additional accel-
erometers will be mounted at the corners of the vehicles
to determine the predominant vibration directions of the
tested vehicles. This data will allow us to determine the
contributions of vertical, pitch, and roll suspension modes
of vibration.
The road inputs determined from test data will also be
used to construct a “torture course” within the Experimental
Mine. It is expected that this test track will consist of coarse
gravel, fine gravel, 2x4s, speed bumps, and curbs. The 2x4s,
speed bumps, and curbs will be arranged to elicit the vehi-
cle motion observed in the field. NIOSH will instrument
one or more of its MUVs to conduct in-house testing on
the test track. To verify that the vibration isolation designs
reduce LIB vibration, vehicle vibration tests will be con-
ducted using the test track.
CONCLUSIONS
LIBs are being implemented in the mining industry on
MUVs and RTMs. Because the mining environment is
severe in terms of mechanical shock and vibration, tem-
perature range, and relative humidity, research must be
performed to examine the environmental susceptibility of
LIBs used on these vehicles. Existing standards/regulations
may not be representative of field conditions. Therefore,
field testing must be performed to determine actual oper-
ating mechanical shock and vibration levels, temperatures,
and relative humidity values for tests. By subjecting LIBs
to a comprehensive environmental test, the environmental
susceptibility of LIBs can be assessed. LIB isolation systems
can be installed on MUVs/RTMs, if necessary. The informa-
tion resulting from this effort can be used by mines, equip-
ment manufacturers, and battery suppliers to improve LIB
designs and to reduce the likelihood of adverse LIB events.
LIMITATIONS
The research project described above will not necessarily
prevent all adverse LIB events. Manufacturing defects will
not be addressed. In addition, field testing will be conducted
at a small number of mines relative to the entire population
of mines. Through laboratory testing, this research intends
to evaluate only the environmental effects that are expected
to be most critical, such as mechanical shock and vibration,
temperature extremes, and moisture exposure, and only
within a range of each of these parameters. Therefore, the
worst-case conditions may not be identified.
DISCLAIMER
The findings and conclusions in this paper are those of the
authors and do not necessarily represent the official posi-
tion of the National Institute for Occupational Safety
and Health, Centers for Disease Control and Prevention.
Mention of any company or product does not constitute
endorsement by NIOSH.
necessary height and release it so that it free falls onto the
test surface. To subject LIBs to shock and vibration, a com-
mercially available hydraulic or electromechanical shaker
and a suitable controller will be purchased. The tempera-
ture/relative humidity chamber will be designed to encap-
sulate the moving portion of the shaker. The immersion test
apparatus will consist of a platform that lowers the tested
LIB into a suitably sized container of liquid.
During testing, the LIB will be monitored to exam-
ine surface and, possibly, internal temperatures. A thermal
imaging camera will be used for surface temperature mea-
surement. Multiple thermocouples will also be attached to
the battery case and, if possible, to cells within the bat-
tery case. Pressure sensors may also be used inside the
case because any venting of LIB cells inside is expected to
increase the internal pressure of the case. At this time, we
expect to conduct the tests with the battery management
system activated.
Numerous safety measures will be taken to protect
researchers and test equipment. The facility will use a video
monitoring system so that researchers can remain outside
the test chamber during tests. A ventilation system will be
installed to allow fresh air to flow into the test chamber and
contaminated air to flow out through an existing borehole.
Gas monitoring equipment will be installed within the test
chamber to ensure the atmosphere is safe for researchers to
enter.
Mine Utility Vehicle/Rubber-tired Mantrip Battery
Protection
To protect LIBs on MUVs/RTMs from excessive mechani-
cal shock and vibration, vibration isolation systems will be
designed. For this effort, dynamic simulation models of the
vehicles will be developed to predict the vibration response
at the LIB on the machine with and without vibration iso-
lators in place. Simulations will be conducted to determine
appropriate isolator parameters such as spring rate and
damping. Tire and suspension characteristics and vehicle
weight will be obtained from cooperating manufacturers or
determined via testing and measurement.
For the simulations, the approximate road inputs
will be derived from field conditions using measurements
of speed and resulting vibration response. In addition to
the shock and vibration recorded using the environmental
data recorders, on selected MUVs/RTMs additional accel-
erometers will be mounted at the corners of the vehicles
to determine the predominant vibration directions of the
tested vehicles. This data will allow us to determine the
contributions of vertical, pitch, and roll suspension modes
of vibration.
The road inputs determined from test data will also be
used to construct a “torture course” within the Experimental
Mine. It is expected that this test track will consist of coarse
gravel, fine gravel, 2x4s, speed bumps, and curbs. The 2x4s,
speed bumps, and curbs will be arranged to elicit the vehi-
cle motion observed in the field. NIOSH will instrument
one or more of its MUVs to conduct in-house testing on
the test track. To verify that the vibration isolation designs
reduce LIB vibration, vehicle vibration tests will be con-
ducted using the test track.
CONCLUSIONS
LIBs are being implemented in the mining industry on
MUVs and RTMs. Because the mining environment is
severe in terms of mechanical shock and vibration, tem-
perature range, and relative humidity, research must be
performed to examine the environmental susceptibility of
LIBs used on these vehicles. Existing standards/regulations
may not be representative of field conditions. Therefore,
field testing must be performed to determine actual oper-
ating mechanical shock and vibration levels, temperatures,
and relative humidity values for tests. By subjecting LIBs
to a comprehensive environmental test, the environmental
susceptibility of LIBs can be assessed. LIB isolation systems
can be installed on MUVs/RTMs, if necessary. The informa-
tion resulting from this effort can be used by mines, equip-
ment manufacturers, and battery suppliers to improve LIB
designs and to reduce the likelihood of adverse LIB events.
LIMITATIONS
The research project described above will not necessarily
prevent all adverse LIB events. Manufacturing defects will
not be addressed. In addition, field testing will be conducted
at a small number of mines relative to the entire population
of mines. Through laboratory testing, this research intends
to evaluate only the environmental effects that are expected
to be most critical, such as mechanical shock and vibration,
temperature extremes, and moisture exposure, and only
within a range of each of these parameters. Therefore, the
worst-case conditions may not be identified.
DISCLAIMER
The findings and conclusions in this paper are those of the
authors and do not necessarily represent the official posi-
tion of the National Institute for Occupational Safety
and Health, Centers for Disease Control and Prevention.
Mention of any company or product does not constitute
endorsement by NIOSH.